Testing dextromethorphan for treating OCD and related disorders

Fluoxetine/Dextromethorphan in Obsessive-Compulsive and Related Disorders: an Open-Label Crossover Pilot Study

Phase 2 Interventional Stanford University · NCT04899687

This study is testing if adding a common cough medicine called dextromethorphan to the usual OCD treatment can help people with OCD and similar disorders feel better.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment60 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorStanford University Academic / other
Locations1 site (Stanford, California)
Trial IDNCT04899687 on ClinicalTrials.gov

What this trial studies

This study evaluates the effectiveness and tolerability of dextromethorphan, an over-the-counter cough suppressant, when combined with fluoxetine, a standard treatment for obsessive-compulsive disorder (OCD) and related disorders such as body dysmorphic disorder (BDD), illness anxiety disorder (IAD), and somatic symptom disorder (SSD). Participants diagnosed with these conditions will receive the treatment to assess symptom relief. The study aims to address the inadequacies of current treatments for these psychiatric conditions, which significantly impact mental health and daily functioning.

Who should consider this trial

Good fit: Ideal candidates include individuals diagnosed with OCD, BDD, IAD, or SSD who reside in California and can provide informed consent.

Not a fit: Patients with bipolar disorder, psychotic disorders, or severe substance use disorders, as well as pregnant or nursing women, may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new, effective option for patients suffering from OCD and related disorders.

How similar studies have performed: While the use of dextromethorphan in this context is novel, other studies have explored various treatments for OCD and related disorders, indicating potential for success with innovative approaches.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Diagnosis of obsessive-compulsive disorder (OCD), body dysmorphic disorder (BDD), illness anxiety disorder (IAD) or somatic symptom disorder (SSD)
* Living within California
* Capacity to provide informed consent

Exclusion Criteria:

* Current bipolar disorder or psychotic disorder
* Active moderate or severe substance use disorder, lifetime severe substance use disorder
* Pregnant or nursing women
* Use of prescribed psychotropic medications other than fluoxetine for 2 weeks prior to study start
* Having commenced OCD-targeted exposure and response-prevention (ExRP) psychotherapy within 2 months of study start

Where this trial is running

Stanford, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Obsessive-Compulsive DisorderIllness Anxiety DisorderBody Dysmorphic DisordersSomatic Symptom DisorderOCDBDDIADSSD
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.